The present invention has application generally to a rail vehicle for a freight train, and more particularly, a rail vehicle which is configured for ease of loading and unloading freight, especially in the form of semi-trailers. Such a rail vehicle has utility in and of itself, and can also configured for use particularly in an integral/semi-integral train employing a segmented roll-on/roll-off freight loading/unloading system. Generally, multiple rail vehicles can be articulated together to form a segments of an integral train for carrying freight, such as semi-trailers, wherein each such segment has an integrated arrangement composed of different types of rail vehicle platforms, including an adapter platform, intermediate platforms and a loading ramp platform. Such an integral train is disclosed in copending U.S. patent application Ser. No. 09/225,204, filed Feb. 22, 1999, which is hereby incorporated herein by reference. Additionally, such a rail vehicle particularly configured for roll-on/roll-off freight loading/unloading can also be designed suitably for use with conventional rail cars which are not part of such an integral train. In fact, the present great majority freight cars typically utilized for transport of such semi-trailers are of the common variety, i.e., not part of an integral train segment. Furthermore, an added feature of such a ramp car rail vehicle can be a draft arm and coupler arrangement particularly adapted for use on the ramp end of the ramp car.
Adapter, intermediate and ramp platform rail car platforms are provided for forming an integral train segment, is provided for carrying standard over-the-highway semi-trailers An intermodal train can have a standard locomotive pulling one or more identical integral train segments. Each integral train segment can have eleven or more platforms and may be loaded or unloaded independently of any other segment using a self contained, roll-on/roll-off system This system can have an integral ramp on at least one end of each segment, for use by a hostler tractor and/or the semi-trailers as they are being loaded or unloaded. The platforms which make up each segment can be connected by articulated joints so as to eliminate longitudinal slack and reduce costs. At least one platform should be equipped with a standard knuckle coupler at standard height to permit the segments to be pulled by any existing locomotive.
In order to permit carriage of non-railroad trailers, a very good ride quality is required; and this can be provided by premium trucks and a low 36xc2xd inch deck height, both of which combine to permit stable operation at high speed. High speed operation is also made possible by a brake system providing actual train average braking ratios of eighteen percent nearly double that available with standard equipment. Use of this braking system can permit the Steel Turnpike to operate at speeds thirty percent higher than AAR standard freight trains, while stopping within the same distance. High speed operation is worthless in the service sensitive trailer market, however, if extremely high reliability is not possible. In order to provide this reliability, a continuously operating health monitoring system can be provided. This system signals potential problems to the operator as soon as they arise, thus permitting timely maintenance to correct defects that would otherwise cause delays, damage or equipment out-of-service problems. Properly functioning, the continuous monitoring system is capable of generally eliminating two of the most significant causes of derailment, namely broken wheels and burned off journal bearings.
It is envisioned that intermodal trains will normally consist of several segments to produce trains of over one hundred trailer capacity. In operation, advantage can be gained by using these segments in pairs with the two ramp platforms connected to each other, as will be further discussed.
Each intermodal train segment can consist of three platform types, articulated together. The first platform type is the xe2x80x9cadapter platform,xe2x80x9d which can have a 28 inch low conveyance truck, a conventional knuckle coupler, hydraulic draft gear, carbody bolster and centerplate at one end (hereinafter referred to as the A-end); and a 33 inch truck with high capacity bearings and a female half spherical articulated connector with combined center plate (Cardwell SAC-1 type) at the other end (hereinafter referred to as the xe2x80x9cB-endxe2x80x9d). The adapter platform is intended to be coupled behind a standard locomotive or rail car.
The second platform type is an xe2x80x9cintermediate platformxe2x80x9d which can have a female articulated (SAC-1) connection and a single 33 inch truck, identical to that on the B-end of the adapter car. A male articulated connection without truck is provided at the A-end, which is supported by the mating female articulation and truck at the B-end of an adjacent platform.
The third type platform is a xe2x80x9cramp loader platform,xe2x80x9d which is similar to the intermediate platform in that it too has only one truck at the B-end, but differs in that it is a 28 inch low conveyance type truck which may have a special bolster with a low counterplate. Since this truck supports only about half the weight borne by those of the intermediate units, the wheels can be smaller without danger of overloading wheels, axles or bearings. The A-end of the ramp platform can have a male articulated connection to be supported by the B-end of an adjacent platform, in like manner as the intermediate platform. At the B-end of the ramp platform, the deck extends beyond the truck, and is supported by a carbody bolster and centerplate which may be of either standard or lower than standard height above top of rail, rather than an articulated connection. Use of the 28 inch truck at the B-end location allows the deck height of the end of the ramp platform car to be reduced from the 36xc2xd inch height of the rest of the train down to 31xc2xd inches at the B-end truck centerline. This height can be further reduced by angling the extended deck toward the ground, resulting in a final deck height at the end sill of only 17xc2xc inches.
Since the B-end of the ramp platform is so much lower than the normal 34xc2xd inch coupler height, an unconventional coupler arrangement is required, particularly if it is to be coupled to a conventional locomotive or cars. Two configurations are proposed, the first using a standard knuckle coupler carried in a hinged beam which also carries a standard draft gear. The second configuration involves using a simple rapid transit type coupler carried well below the normal 34xc2xd inch height. The latter is mechanically much smaller than the hinged beam structure, but only permits the coupling of the ramp platform to a second ramp platform having a similar low placed transit coupler.
Furthermore, an individual rail vehicle can be designed generally corresponding to the ramp platform segment of the integral train segment described above. Such rail vehicle can include many of the features of the ramp platform integral train segment, but can be distinct in that it is capable of use apart from such integral train segment. Such a ramp car rail vehicle may also be supported by a truck at both ends of the vehicle and further may include a coupler at either end for being coupled in a conventional manner to other conventional rail cars which may commonly be used to transport freight in the form of the semi-trailers described above. Such a ramp car rail vehicle would thus have a greater degree of utility because of the compatibility with existing railway freight transportation systems, rather than being limited to use as a component of an integral train segment. At the same time the gap between the end of such a car and the conventional car(s) would require the use of bridge plates to carry the tires of truck trailers being loaded over the wide space between the sills of any conventionally coupled pair of cars.
Other details, objects, and advantages of the invention will become apparent from the following detailed description and the accompanying drawing Figures of certain embodiments thereof.